12.3 HII Protocols
Some protocols must be clearly understood in order to successfully implement a
UEFI driver with HII functionality. The basic protocols consist of four
consumable protocols and the HII Config Access Protocol produced by a UEFI
Driver. They need not be used in any particular order. The MdeModulePkg
provides the UefiHiiServicesLib
that automatically looks up consumed HII
protocols and makes them available to a UEFI Driver requiring the services they
provide. A UEFI platform is not required to produce all of these protocols. The
following is the list of protocols and the global variable provided by the
UefiHiiServicesLib
. If a global variable is set to NULL
, it means that the
platform does not produce that specific protocol. UEFI Drivers must handle all
platform configurations, so it is important for a UEFI Driver to continue to
function both when an HII related protocol is present and when an HII related
protocol is absent.
EFI_HII_DATABASE_PROTOCOL gHiiDatabase
EFI_HII_STRING_PROTOCOL gHiiString
EFI_HII_FONT_PROTOCOL gHiiFont
EFI_HII_IMAGE_PROTOCOL gHiiImage